Unlike other companions, she both fell in love with the Doctor and declared that affection. Because he pointedly failed to return that affection, she eventually decided to part company with him. (TV: Last of the Time Lords)

During his final reward, in which the slowly dying Tenth Doctor visited his companions, he saw Mickey and Martha fighting off a Sontaran invasion. By this time, Smith and Jones were "freelance" defenders of Earth, unaffiliated with any organisation. (TV: The End of Time)

Biography

Early life

Martha Jones was born in 1986 to Francine and Clive Jones. She had an older sister called Tish, a younger brother, Leo, and a niece, Keisha Jones. When she was a child, Leo pushed Martha off the swing and broke her arm. Going in the ambulance and having her arm plastered fascinated her. She decided to be a doctor right then. (PROSE: The Story of Martha) Martha's parents divorced when she was young. Her siblings and she grew up with their mother. Martha slept in their home's smallest room. (PROSE: Wooden Heart)

As the oxygen in the hospital ran out, Martha gave her last breaths to resuscitate the clinically-dead Doctor, who had thwarted Florence's plan. The Judoon returned the hospital to Earth. That evening, after another family argument at her brother Leo's party, a recovered Martha was approached by the Doctor, who revealed that he was a Time Lord and invited her to join him on a single trip through time and space in the TARDIS, (TV: Smith and Jones) though he kept extending this "single trip". (TV: Gridlock, Daleks in Manhattan)

After the Cult of Skaro's defeat, the Doctor returned Martha home twelve hours after she had left. He overheard a TV news story about a man promising to "change what it means to be human", and escorted her to the presentation of Prof. Richard Lazarus' rejuvenation device. Uncovering the disastrous effects of Lazarus' work, the Doctor, Martha and her sister Tish helped to kill the monster Lazarus had become. Afterward, the Doctor offered Martha one more trip, but she refused. She no longer wanted to be just a passenger. The Doctor invited her on board the TARDIS, as a full-time companion. (TV: The Lazarus Experiment)

They answered a distress signal in the 42nd centuryTorajii system: a ship falling towards the sun. The sun was a sentient being possessing the crew members and killing them off, but Martha and the Doctor saved the ship and departed safely. During this adventure, Martha had a brief romance with one of the ship's crew, Riley Vashtee. He wanted her to stay but she chose to remain with the Doctor. (TV: 42)

To escape the Family of Blood, who were hunting him, the Doctor used the Chameleon Arch to turn himself into a human being with no memory of the Doctor. He became John Smith, a teacher at an English public school in 1913, where Martha took a job as a maid. Martha watched helplessly as Smith fell in love with a nurse, Joan Redfern, exclaiming he "had to go and fall in love with a human and it wasn't me".

When the Family of Blood tracked them down, wreaking havoc on the town and school, Martha convinced John Smith to sacrifice his human life and love by reverting to the Doctor. He defeated the Family of Blood, left a heartbroken Joan and rejoined Martha in the TARDIS. (TV: Human Nature / The Family of Blood)

Martha and the Doctor travelled to an old house in Wester Drumlins where Weeping Angels sent them back to 1960s London. The Doctor helped Sally Sparrow recover the TARDIS in the future while Martha took a job in a shop to support them. (TV: Blink)

Following a short pit-stop in Cardiff, the TARDIS took Martha and the Doctor to the end of the universe and the planet Malcassairo, where they met Captain Jack Harkness. They also encountered the last humans in the universe, being assisted by Professor Yana. Martha noticed he had a watch similar to the Doctor's Chameleon Arch, prompting him to open it. The human Yana was transformed back into the Doctor's Time Lord nemesis, the Master, and escaped in the TARDIS. (TV: Utopia)

Martha, Jack, and the Doctor used Jack's vortex manipulator to travel back to 21st century Earth the day after Harold Saxon was voted Prime Minister. Mr Saxon was in fact an alias of the Master, who had been living on Earth for months since his departure from Malcassairo. The Master, who had been manipulating Martha's family since she became a full-time companion, had Francine, Clive, and Tish arrested while Leo escaped. As her family, Jack, and the Doctor were all taken prisoner aboard the Valiant, Martha teleported back to Earth with a mission to defeat the Master. (TV: The Sound of Drums)

Martha knew what she had to do: spread the word of the Doctor. In her travels, she visited the ruins of New York City, fusion camps in China and toxic pits in Europe. She travelled from England to rebel camps in Europe, where she met the Brigadier's son Calvin. She was interned in a concentration camp in Japan. After a year travelling around the world, she met fellow resistance member Tom Milligan. (PROSE: The Story of Martha) She had spent a year on Earth telling everyone to think of the Doctor at a specific time so the Master could be defeated. This plan worked; the Doctor returned to his original form and the Master was shot by his wife, Lucy Saxon. As a result of the destruction of the Master's paradox machine, only Martha, her family, and the people on board the Valiant retained their memories of that year under the Master.

Although the Doctor wanted her to stay with him, she felt her family needed her more. She also needed to get out of what she saw was an unhealthy relationship of her hoping the Doctor would finally notice her. She stayed on Earth to complete her training as a doctor. To keep in touch, she gave the Doctor her superphone saying that she would call him when she needed him. (TV: Last of the Time Lords) The Eleventh Doctor later felt guilty about how he had treated her during the time they travelled together. (TV: Let's Kill Hitler)

Martha was recruited by UNIT. She and Captain Jack believed the Tenth Doctor put in a good word for her. She visited Torchwood Three in Cardiff as a UNIT officer. She became embroiled in their investigation of a medical organisation called the Pharm as an undercover agent. She was discovered and captured, and Mayflies were put into her body. Owen Harper saved her life with an alien surgical device. As Aaron Copley attempted to shoot Martha, Owen saved her by taking the bullet for her. He was killed. Before Copley could shoot Martha, he was shot by Jack. (TV: Reset)

Martha witnessed Owen's return as an undead being through the resurrection gauntlet. She gave him a posthumous physical. "Death", a force possessing Harper, made the gauntlet attack Martha and age her into an old woman. After Owen defeated the Death being, she reverted to normal (TV: Dead Man Walking). She mended Harper's injured hand when, in a fit of self-destruction after Jack decided to relieve him of duty at Torchwood, he deliberately wounded it.

Once Owen Harper was returned to duty, she left for UNIT, a few days after she had begun working with them. (TV: A Day in the Death)

Martha's clone died soon after the Doctor rescued Martha, but Martha was able to convince the clone to help them. Before the clone died, it said Martha had many things she wanted to do and she should do them. While chatting with the Doctor and Donna after the Sontarans' defeat, Martha turned down the Doctor's offer to travel again with him. As soon as she had made her refusal, an unknown force took control of the TARDIS, and dragged them into the Time Vortex. (TV: The Poison Sky)

Martha walked out of the TARDIS onto the planet Messaline, remarking that even though she didn't want to travel with the Doctor any more, she loved the first step on a new planet. The Doctor was grabbed and his hand put in a machine to form his daughter, Jenny. Soon after, they were attacked by the Hath. Martha was separated from the Doctor and Donna and taken by the Hath. She helped the injured Hath Peck, earning the Hath's trust. They showed her a map of their location.

The Doctor was shown a corresponding map, and made new passages and tunnels appear on both maps. The Doctor phoned Martha and told her where they were heading. Martha went onto the planet's surface and took Hath Peck with her. She slipped into a pool of quicksand, but Hath Peck saved her life, sacrificing his own. Martha found the Temple and was reunited with the Doctor, Donna, and Jenny. They discovered what the humans and Hath were fighting over: the Source, a terraforming device which would make the planet's surface habitable.

As the Hath and the humans appeared, the Doctor released the Source. General Cobb was enraged and shot at the Doctor, killing Jenny instead. When the Doctor said that there was a possibility she would come back to life, Martha shook her head and confirmed she was dead. The Doctor returned Martha to Earth. She said a fond farewell to Donna and him, and went off to reunite with her fiancé, Thomas Milligan. (TV: The Doctor's Daughter)

Martha moved to New York after promotion to the post of Medical Director on Project Indigo, a teleport device using recovered Sontaran technology. Whilst she was working at UNIT HQ in New York City, Earth was transported to the Medusa Cascade.

When Daleks attacked the base, General Sanchez ordered Martha to use Project Indigo to escape and contact the Doctor. Sanchez also gave her the Osterhagen Key and ordered her to use it should the need arise. Project Indigo, which had never been tested, teleported Martha to her home in London, where she was reunited with her mother. Martha later theorised that her emotions controlled it, sending her home.

Unsure of whether the Doctor would come, Martha decided to use the Osterhagen Key. Leaving her mother, she teleported to Germany and a secret UNIT base — one of several Osterhagen Key activation points.

Martha and two other UNIT operatives in other locations prepared to activate the Osterhagen Project, but first she contacted the Crucible, warning the Daleks and Davros she would use the key to destroy Earth rather than let it fall into their hands. They teleported her to the Crucible, however. Here, she was joined with the Doctor, Rose Tyler, Mickey Smith, Jackie Tyler, Jack, and Sarah Jane. After the arrival of Donna and the Meta-Crisis Tenth Doctor, they defeated the Daleks and their plans. Martha and the others assisted the Doctor in piloting the TARDIS, towing Earth back to its solar system. (TV: Journey's End)

Return to UNIT and Freelance Work

After Earth was returned to its proper place, Martha exited the TARDIS with Jack Harkness, who offered her a job with Torchwood. She did not take Jack's offer to work for Torchwood, but stayed with UNIT.

She phoned Captain Jack when stationed at the CERN Facility in Switzerland when the Large Hadron Collider was scheduled to be activated. Some of the staff had gone missing, including her old friend Julia Swayles. The Torchwood 3 team went to Switzerland to investigate and found the person who was responsible was Dr. Harrington. (AUDIO: Lost Souls)

She decided to go into "freelance" alien fighting with Mickey Smith, whom she had married. One adventure saw Martha and Mickey battle a Sontaran, Jask. Unknown to them, Jask had them cornered and was about to kill them. The Doctor stepped in and knocked out Jask, saving them as his final gift to them prior to his next regeneration . Martha spotted the Doctor. They called out to him, but he walked away without saying a word. As the TARDIS left, Martha embraced her husband sadly, possibly realising what the Doctor's appearance meant. (TV: The End of Time)

If Donna Noble had turned right for a job interview instead of turning left, Martha would still have been working in the Royal Hope Hospital at the time that the hospital was moved to the Moon by the Judoon. In this timeline, she would have met Sarah Jane and Luke Smith, as well as Maria Jackson and Clyde Langer, as they investigated the hospital. When the oxygen ran out, everyone in the hospital, including Martha, would be left to die of suffocation. She would have given the last oxygen tank to fellow student Oliver Morgenstern before dying, leaving him the only survivor. (TV: Turn Left)

Personality

Martha was an intelligent, brave and kind-hearted woman with a great sense of humour. When she was a prisoner of the Daleks, one of them confirmed that she possessed high intelligence. (TV: Daleks in Manhattan) The Doctor was impressed with her theory about having air on the Moon, and he asked her to join him in the hospital balcony to see if they could breathe. (TV: Smith and Jones) Although the Doctor asked more of her than any other companion (watching after him while he was human, walking the world for a year), she rose to every challenge. (TV: Human Nature, Last of the Time Lords)

Martha was anti-racist, willing to accept non-humans as aliens... even when they looked odd. (TV: Utopia)

Martha quickly developed a crush on the Doctor and always wondered if he even noticed her. Martha was envious of Joan Redfern when the Doctor made himself a human named John Smith and fell in love with her. She said he "had to go and fall in love with a human, and it wasn't me". (TV: Human Nature/The Family of Blood)

Although she had cause to be jealous of Rose Tyler, Martha seemed genuinely happy for the Doctor when he and Rose were reunited. She got along very well with Donna Noble. After the year that never was, Martha became a close friend of Captain Jack Harkness and although she did not seem to return his overtures, she did not mind when he flirted with her. (TV: Utopia)

Martha's last scene in Journey's End was interpreted as opening the door for a possible return to Torchwood. Although there were unconfirmed rumours that Agyeman was seen at a Torchwood filming location, she did not appear in the Children of Earth miniseries; she was referenced in dialogue as being still with UNIT. Her subsequent appearance at the end of TV: The End of Time again fueled speculation of a possible future Torchwood appearance, which did not come about in the revived Torchwood.

Interestingly, the name 'Martha Jones', is an anagram of 'A Master John'. This may be a reference to the Master, played by actor John Simm in the Series Three finale.

Multi-adventures reference the rare instance when a companion is shown or stated to have multiple adventures with the Doctor but only appears in a single story.
If a medium is not mentioned, then this incarnation did not have companions who were original to that medium; it does not mean that this Doctor failed to appear in that medium.